Installing Kubuntu

Warning: During installation, there is an advanced option (Ready to install -> Summary -> Advanced) to install the GRUB2 bootloader into the same partition into which the (K)Ubuntu OS is installed but not to change the MBR (Master Boot Record). Pay careful attention during this step if your system uses a boot partition, uses multiple OS (more than 2), or chainloads bootloaders. For systems with such a boot partition, it is best not to overwrite the MBR.

Hardware requirements

Kubuntu Oneiric Ocelot runs with as little as 384 Mb RAM. (The GUI installer requires a minimum of 256 Mb RAM, while the alternative text-based installer can run using only 192 Mb RAM.)

The installation takes between 3-4 Gb hard drive space, and 8-10 Gb will be needed to run comfortably. (However, at least 25-30 Gb will likely be needed for routine usage.)

Netbooks will run Kubuntu Oneiric Ocelot, which has been optimised for speed, efficiency, and quick bootup. An interface optimised for Netbooks is available as an option.

If you have an older computer with less memory than this, consider Lubuntu (if 160 Mb RAM or greater), PuppyLinux (if 256 Mb or greater), or DSL (if minimal RAM, limited hard drive space, running from a USBdrive, or running from within another OS).

Fresh Installation

Kubuntu Oneiric Ocelot contains the KDE 4 desktop by default. The desktop has been improved and many bugs fixed since earlier versions of KDE 4. In addition, the incorporated Linux kernel is more efficient and more hardware is recognized by default. Especially on a smaller system with limited hard drive space, a new installation is recommended to prevent software bloat that can accumulate when updating older versions.

The Alternate CD version also allows the use of the same fast text-based installer used in the Server version (requiring less RAM), and there are more installation options than on the Desktop CD ("Regular Download").

Trinity Desktop (KDE 3 Remix)

Kubuntu Hardy Heron LTS used a simpler but well-respected stable desktop, KDE 3.5. This desktop environment has been renamed the Trinity Desktop Environment and is available for all versions of Kubuntu. Installation is accomplished using the Trinity PPA repositories.

Dual-Booting Windows and Kubuntu

A user may experience problems dual-booting (K)Ubuntu and Windows. In general, a Windows OS should be installed first, because its bootloader is very particular. A default Windows installation usually occupies the entire hard drive, so the main Windows partition needs to be shrunk, creating free space for the (K)Ubuntu partitions. (You should clean up unnecessary files and defragment the drive before resizing.) See changing the Windows partition size.

After shrinking a Windows partition, you should reboot once into Windows prior to installing (K)Ubuntu or further manipulating the partitions. This allows the Windows system to automatically rescan the newly-resized partition (using chkdsk in XP or other utilities in more recent versions of Windows) and write changes to its own bootup files. (If you forget to do this, you may later have to repair the Windows partition bootup files manually using the Windows Recovery Console.)

Newer installations of Windows use two primary partitions (a small Windows boot partition and a large Windows OS partition). A (K)Ubuntu Linux installation also requires two partitions -- a linux-swap partition and the OS partition. The Linux partitions can either be two primary partitions or can be two logical partitions within an extended partition. Some computer retailers use all four partitions on a hard drive. Unless there are two free partitions available (either primary or logical) in which to install (K)Ubuntu, however, it will appear as if there is no available free space. If only one partition on a hard drive can be made available, it must be used as an extended partition (in which multiple logical partitions can then be created). Partition management can be done using the GParted utility or KDE Partition Manager.

If there are only two existing primary partitions on a hard drive (and plenty of free space on it) then there will be no problem installing (K)Ubuntu as the second operating system and it is done automatically from the (K)Ubuntu LiveCD. Allow the (K)Ubuntu LiveCD to install to "largest available free space." Alternatively, if there is an extended partition with plenty of free space within it, the (K)Ubuntu LiveCD will install to this "largest available free space" as well.

The main Windows partition should be at least 20 Gb (recommended 30 Gb for Vista/Windows 7), and a (K)Ubuntu partition at least 10 Gb (recommended 20 Gb). Obviously, if you have plenty of disk space, make the partition for whichever will be your favoured operating system larger. For a recommended partitioning scheme, see this section.

Alternatives include:

Wubi (Windows-based Ubuntu Installer), an officially supported dual-boot installer that allows (K)Ubuntu to be run mounted in a virtual-disk within the Windows environment (which can cause a slight degradation in performance). Because the installation requires an intact functioning Windows system, it is recommended to install (K)Ubuntu in this manner for short-term evaluation purposes only. A permanent (K)Ubuntu installation should be installed in its own partition, with its own filesystem, and should not rely on Windows.

Installing multiple OS on a single computer

Warning: During installation, there is an advanced option (Ready to install -> Summary -> Advanced) to install the GRUB2 bootloader into the same partition into which the (K)Ubuntu OS is installed but not to change the MBR (Master Boot Record). Pay careful attention during this step if your system uses a boot partition, uses multiple OS (more than 2), or chainloads bootloaders. For systems with such a boot partition, it is best not to overwrite the MBR.

Example, from the Desktop version GUI installer, a point in the installation will be reached:

In this example, this setting will cause the GRUB2 bootloader to be installed into /dev/sda6 only (the partition into which the new (K)Ubuntu OS is being installed). The MBR (Master Boot Record) will not be changed. However, if the default setting of /dev/sda is allowed, then GRUB2 will not only be installed into partition dev/sda6 (into which the (K)Ubuntu OS is installed) but also the MBR (MasterBootRecord) will be changed so that the copy of GRUB2 stored there will be designated as the master bootloader for all Operating Systems on the entire computer. This may be undesirable if you wish to use bootloaders other than GRUB2.

Upgrading from older versions

There are several methods for upgrades from the command-line interface (Konsole) (which can be used for both the desktop and server editions of Kubuntu/Ubuntu).

This is the preferred method:

sudo apt-get install update-manager-core
sudo do-release-upgrade

You can also use the update-manager (all editions):

sudo apt-get install update-manager
sudo update-manager -d

You can also use:

sudo apt-get update
sudo apt-get upgrade
sudo apt-get dist-upgrade

(Note: the first two lines simply make sure your current distribution is current before upgrading the entire distribution, and are optional.

Always backup your system. Upgrades do not generally work for me, because I often make customizations to my older installations (to make my hardware work with them) but these customizations are often not required in the newest version. When the system then attempts to migrate my customizations (during an attempted upgrade), it often crashes my new system. (Fortunately, I always back up my important files, and reinstalling them on a fresh OS installation is therefore usually accomplished relatively quickly.) Here are some of the steps I have sometimes needed to take when performing upgrades.

In general, upgrades must be done serially from one version to the next in order.